1. Field of the Invention
The present invention relates to a moving picture data processing apparatus, a stream generating apparatus, an imaging apparatus, and a moving picture data processing method for processing moving picture data. Particularly, the invention is directed to a moving picture data processing apparatus, a stream generating apparatus, an imaging apparatus, and a moving picture data processing method, all capable of processing moving picture data for which screen rates are switchable.
2. Description of Related Art
Recently, imaging apparatus (digital video cameras) capable of imaging moving pictures for recording as digital data has become popular rapidly. Some of such imaging apparatus additionally record imaged time information, that is, information of the time when imaging is performed, in a stream into which video data and audio data are multiplexed, and read the information during playback to display the imaged times onscreen. One such example is an apparatus that generates a multiplexed stream into which an additional recording information pack containing imaged time information is multiplexed together with video packs and audio packs (see, e.g., Japanese Patent Application Publication No. 2005-79823 (Paragraphs Nos. [0047]-[0050] and FIG. 8).
Furthermore, the imaged time information to be thus recorded in a multiplexed stream is generated as follows. That is, when recording of an imaged picture on a recording medium has been started, a recording start time is read from a clock built in an imaging apparatus, and then a fixed time corresponding to a cycle for outputting a picture frame is added to the recording start time every time the cycle occurs. According to this method, even if the built-in clock is not accurate enough, correct time information has been recorded in synchronism with the cycle for outputting a picture frame, at the time the multiplexed stream is generated.
Meanwhile, as the performance of an imaging device and the signal processing technology progress, such imaging apparatus as mentioned above come to be able to output an imaged picture at a display cycle shorter than that defined by the current TV broadcasting standard. Hence, an imaging apparatus with such a fast imaging function is being contemplated. For example, an imaging apparatus capable of slow playback is in contemplation, in which video data imaged and recorded at a screen rate several times a standard screen rate are played back and displayed at the standard screen rate.